Yes, you can grab more time for this. As soon as you think that Gray might be about to reappear again, back out from the puzzle and go out to the corridor to hit the alarm button again. Then return to the puzzle and carry on where you left off. Repeat this over as necessary until you've completed the colour puzzle.

thanks got through the colours have gotten to air duct am stuck at going through air duct in tunnel will keep trying if not will call on you later thanks wow what a game. gja oh sorry happy new year to all.

Glad you made it past the colour puzzle, Gemma. Good luck with the air duct! Remember to move forward until you're able to make your next turn left or right, if you're following the walkthrough directions.